Thin-Walled Structures最新文献

Comparative study on collapse behavior of modular steel buildings: Experiment and analysis 模块化钢结构建筑倒塌行为比较研究：实验与分析

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-16 DOI: 10.1016/j.tws.2024.112695

Zhi-Wei Yu , Wei-Lin Ma , Jing-Zhou Zhang , Zhen Tian

With the increasing adoption of modular construction technology, understanding the modular steel buildings' collapse mechanisms has become crucial. This study presents comparative collapse tests on two modular steel substructures: specimen in corner column loss (S-CCL) and specimen in side column loss (S-SCL). The failure modes, load-bearing capacities, lateral displacements of modules, relative slips of double-layer beams, and deformation mechanisms of the components were compared. The findings reveal significant buckling at the ends of module beams far from the column loss area in both specimens, with minor buckling near the column loss area. No bolt hole fracture is observed in S-CCL, while S-SCL exhibits clear fractures. S-SCL demonstrates approximately double the load-bearing capacity of S-CCL during the elastic stage, and this increases further in the elastoplastic stage due to catenary action, ultimately reaching three times that of S-CCL. Significant lateral displacement occurs only in the double-span beam direction of S-SCL, towards the column loss area, while in other directions, displacement is minor and directed away. Digital image correlation (DIC) measurements indicate that relative slip in double-layer beams is significantly smaller in S-SCL compared to S-CCL. Strain gauge readings show that both module columns remain within the elastic range, but columns in S-SCL continue to deform in the plastic stage due to tensile forces in the connected beams, with beam ends away from the column loss area experiencing negative bending moments.

随着越来越多地采用模块化建筑技术，了解模块化钢结构建筑的倒塌机理变得至关重要。本研究介绍了两种模块化钢结构下部结构的倒塌对比试验：角柱损失试样（S-CCL）和侧柱损失试样（S-SCL）。比较了模块的破坏模式、承载能力、横向位移、双层梁的相对滑移以及组件的变形机制。研究结果表明，在两种试样中，远离支柱损失区域的模块梁端部都出现了明显的屈曲，而在支柱损失区域附近则出现了轻微的屈曲。在 S-CCL 中未观察到螺栓孔断裂，而 S-SCL 则表现出明显的断裂。在弹性阶段，S-SCL 的承载能力约为 S-CCL 的两倍，在弹塑性阶段，由于导管作用，承载能力进一步提高，最终达到 S-CCL 的三倍。只有在 S-SCL 的双跨梁方向上才会出现明显的横向位移，即向支柱损耗区方向位移，而在其他方向上，位移较小，而且是向远处位移。数字图像相关测量（DIC）表明，与 S-CCL 相比，S-SCL 双层梁的相对滑移要小得多。应变仪读数显示，两个模块的柱子都保持在弹性范围内，但 S-SCL 中的柱子在塑性阶段继续变形，这是由于连接梁中的拉力造成的，远离柱子损失区域的梁端出现负弯矩。

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引用次数: 0

Local-global buckling interaction in steel I-beams—A European design proposal for the case of fire 钢工字钢的局部-整体屈曲相互作用--欧洲针对火灾的设计建议

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-15 DOI: 10.1016/j.tws.2024.112664

Carlos Couto, Paulo Vila Real, Nuno Lopes

This paper presents a comprehensive review of the developments leading to the proposal of European fire design rules for steel beams with thin-walled I-sections. Thin-walled beams are favoured in steel construction due to their structural efficiency, however they are prone to buckle when subjected to in-plane loads, phenomenon which requires a thorough investigation. The focus lies on addressing the interaction between local and global buckling in these members. This study discusses modifications to the Effective Width Method at elevated temperatures, aiming to rectify underestimation of section capacity on certain cross-sections. Additionally, an overview of lateral-torsional buckling resistance is provided, being a new Effective Section Factor proposed to account for its interaction with local buckling. The paper revisits the European fire design proposal, comparing the improvements of the existing Eurocode 3 Part 1–2 (EN1993-1-2:2005) relative to the recent second generation of Part 1–2 of Eurocode 3 (FprEN1993-1-2:2023) through an extensive numerical study. Limitations and future research directions are also discussed, such as dependency on the section classification and broadening the application scope of these rules to higher steel grades.

本文全面回顾了欧洲针对薄壁工字钢梁提出防火设计规则的进展情况。薄壁钢梁因其结构效率高而受到钢结构的青睐，但在承受平面荷载时容易发生屈曲，这一现象需要进行深入研究。重点在于解决这些构件的局部和整体屈曲之间的相互作用。本研究讨论了在高温条件下对有效宽度法的修改，旨在纠正对某些截面的截面承载力估计不足的问题。此外，本文还概述了横向扭转屈曲阻力，并提出了新的有效截面系数，以考虑其与局部屈曲的相互作用。本文重新审视了欧洲防火设计建议，通过广泛的数值研究，比较了现有的欧洲规范 3 第 1-2 部分（EN1993-1-2:2005）与最新的第二代欧洲规范 3 第 1-2 部分（FprEN1993-1-2:2023）的改进之处。此外，还讨论了局限性和未来的研究方向，例如对截面分类的依赖性以及将这些规则的应用范围扩大到更高的钢种。

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引用次数: 0

Impact resistance performance of 3D woven TZ800H plates with different textile architecture 不同织物结构的三维编织 TZ800H 板材的抗冲击性能

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-13 DOI: 10.1016/j.tws.2024.112701

Qingbo Guo , Yachen Xie , Mengqi Yuan , Hong Zhang , Tao Wang , Guangyan Huang

Two typical methods commonly used to improve the mechanical properties and impact resistance properties of 3D woven composites are studied, namely weave pattern and layered architectures. The mechanical property and impact resistance performance were studied by utilising the quasi-static compressive test, split Hopkinson pressure bar (SHPB) test and ballistic impact test. The compressive responses in warp and weft directions with different strain rates 0.001, 500 and 1300 s^-1 were presented and analysed, providing strain rate influence on the material strength of different 3D woven composites. The impact resistance performance including damage mode, ballistic limit and specific energy absorption of three structures were discussed through impact tests. The results reveal that as the strain rate increases, the compressive strength and Young's modulus in both directions of 3D woven composites exhibit a significant increase. The compressive strength and modulus in the warp direction of the composites can be enhanced by using shallow interlocking of the warp tow or layered architectures. However, the two methods degrade the failure strain and weaken the strain rate strengthening effect of compressive strength in the weft direction, resulting in a significant decrease in the average strain energy density. For the ballistic impact case, the crimp of warp tows would decrease its load-bearing capacity, while resisting matrix crack growth under the ballistic impact. The significant reduction in the average strain energy density in the weft direction leads to a decrease in ballistic limit and specific energy absorption capacity under ballistic impact.

研究了两种常用于改善三维编织复合材料机械性能和抗冲击性能的典型方法，即编织模式和分层结构。通过准静态压缩试验、分裂霍普金森压力棒（SHPB）试验和弹道冲击试验研究了三维编织复合材料的力学性能和抗冲击性能。结果表明并分析了不同应变速率（0.001、500 和 1300 s-1）下经纬方向的压缩响应，提供了应变速率对不同三维编织复合材料材料强度的影响。通过冲击试验讨论了三种结构的抗冲击性能，包括破坏模式、弹道极限和比能量吸收。结果表明，随着应变率的增加，三维编织复合材料在两个方向上的抗压强度和杨氏模量都有显著增加。复合材料经线方向的抗压强度和模量可以通过经线束的浅交错或分层结构来提高。但是，这两种方法会降低破坏应变，削弱纬向抗压强度的应变率增强效应，从而导致平均应变能密度显著下降。对于弹道冲击情况，经纱束的卷曲会降低其承载能力，同时在弹道冲击下阻止基体裂纹的增长。纬向平均应变能密度的显著降低导致弹道冲击下的弹道极限和比能量吸收能力下降。

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引用次数: 0

Integrated optimization of ply number, layer thickness, and fiber angle for variable-stiffness composites using dynamic multi-fidelity surrogate model 利用动态多保真代理模型综合优化变刚度复合材料的层数、层厚和纤维角度

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-13 DOI: 10.1016/j.tws.2024.112392

Haichao An , Yao Zhang , Qinyun Deng , Teng Long , Byeng D. Youn , Heung Soo Kim

To fully exploit the efficiency of variable-stiffness composite laminates with spatially varied fiber orientation angles, this paper aims at presenting a novel optimization framework for integrated design of ply number, layer thickness, and fiber angle. The optimization problem is innovatively formulated based on the definition of a ground laminate with redundant layers. The basic optimization idea is to seek both unnecessary and necessary layers in this ground laminate. For unnecessary layers, they can be removed and assigned with small-value ply thicknesses, while necessary layers are retained in the ground laminate and corresponding ply thicknesses and fiber angles are optimally determined using discrete and continuous variables, respectively. Since variable-stiffness composite laminates always require high-fidelity analysis models to accurately capture the spatial characteristics of varying fibers, this results in a time-consuming process. To alleviate this problem, a multi-fidelity surrogate model with an exponent-based comprehensive correction is originally proposed based on Gaussian process regression, generating an approximate problem to replace the original one. The genetic algorithm and sequential quadratic programming method are sequentially employed to solve this approximate problem with mixed design variables. The solution from this procedure is dynamically added to the sampling dataset to update the constructed surrogate model. Numerical benchmark problems and cases studies of a composite plate and a solar wing structure are addressed, demonstrating the efficacy of the newly proposed optimization strategy.

为了充分利用具有空间变化纤维取向角的可变刚度复合材料层压板的效率，本文旨在提出一种新颖的优化框架，用于综合设计层数、层厚和纤维角度。优化问题是在定义具有冗余层的地面层压板的基础上创新提出的。基本的优化思路是在该地面层压板中寻找不必要的层和必要的层。对于不必要的层，可将其去除并分配小值层厚，而必要的层则保留在地面层压板中，并分别使用离散变量和连续变量优化确定相应的层厚和纤维角度。由于变刚度复合材料层压板总是需要高保真的分析模型来准确捕捉不同纤维的空间特征，这就导致了一个耗时的过程。为了缓解这一问题，最初提出了一种基于高斯过程回归的多保真度代用模型，该模型具有基于指数的综合修正功能，可生成一个近似问题来替代原始问题。为了解决这个带有混合设计变量的近似问题，先后采用了遗传算法和顺序二次编程法。该程序的解被动态添加到采样数据集中，以更新构建的代用模型。对复合板和太阳能机翼结构进行了数值基准问题和案例研究，证明了新提出的优化策略的有效性。

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引用次数: 0

Developing lightweight steel profile and lattice polymeric core composite for structural use 开发结构用轻质型钢和网格聚合物芯材复合材料

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-10 DOI: 10.1016/j.tws.2024.112697

Ieva Misiūnaitė, Arvydas Rimkus, Viktor Gribniak

Embracing modular construction, advanced materials, and digital technologies can drive innovation in the building industry, address global material consumption challenges, and foster a sustainable future. This paper presents the innovative concept of the lightweight hybrid lattice-filled profile (HLFP) for modular engineering, which combines a thin-walled steel tubular shell and additively manufactured lattice structure (AMLS) as a lightweight core. The AMLS achieves precise shape, internal structure, and stiffness, ensuring the decided structural performance with minimum materials. This study provides a theoretical model of HLFP, focusing on adhesively bonded AMLS. The experimental verification demonstrates that the adhesively bonded AMLS ensures an additional 130 % during the elastic stage and, even after partial debonding, maintains 50 % of the mechanical resistance compared to the theoretical sum of the HLFP components. Reducing the infill density does not severely affect the load-bearing capacity of the HLFP—a fourfold decrease of the ALMS density (from 10 % to 2.5 %) results in a 20 % decrease in the ultimate load. However, the sparse lattice structure alters the failure mechanism of ALMS, changing it from favorable ductile to dangerous brittle and determining the object for further optimization. The parametric study reveals the efficiency of the theoretical model for predicting the load-bearing capacity of HLFP. However, the finite element model developed in this study should be used for a more detailed analysis of the HLFP's structural behavior.

采用模块化建筑、先进材料和数字技术可以推动建筑行业的创新，应对全球材料消耗的挑战，并促进可持续发展的未来。本文介绍了用于模块化工程的轻质混合晶格填充型材（HLFP）的创新概念，它结合了薄壁钢管外壳和作为轻质内核的快速成型晶格结构（AMLS）。AMLS 可实现精确的形状、内部结构和刚度，确保以最少的材料实现最佳的结构性能。本研究提供了 HLFP 的理论模型，重点是粘接式 AMLS。实验验证表明，与 HLFP 各组成部分的理论总和相比，粘合型 AMLS 可确保在弹性阶段增加 130%的机械阻力，即使在部分脱粘之后，也能保持 50%的机械阻力。降低填充密度并不会严重影响 HLFP 的承载能力--ALMS 密度降低四倍（从 10% 降至 2.5%）后，极限荷载降低 20%。然而，稀疏的晶格结构改变了 ALMS 的失效机理，使其从有利的韧性变为危险的脆性，并确定了进一步优化的对象。参数研究揭示了理论模型预测 HLFP 承载能力的效率。不过，本研究开发的有限元模型应用于对 HLFP 结构行为进行更详细的分析。

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引用次数: 0

Free vibration and nonlinear transient analysis of blast-loaded FGM sandwich plates with stepped face sheets: Analytical and artificial neural network approaches 带阶梯面片的爆炸加载 FGM 夹层板的自由振动和非线性瞬态分析：分析和人工神经网络方法

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-10 DOI: 10.1016/j.tws.2024.112667

Peng Shi , Vu Ngoc Viet Hoang , Jian Yang , Haoge Shou , Qi Li , Ferruh Turan

This study investigates the free vibration and transient dynamic response of functionally graded material (FGM) sandwich plates with stepped face sheets (FGM-SPSFS) supported by viscoelastic foundation under blast loading. The research focuses on the effects of geometric configurations and material property variations across segments. Each plate comprises three layers: a homogeneous hard core and two FGM face sheets, divided horizontally into two segments with differing face sheet thicknesses, which enhance structural stiffness while maintaining a consistent total thickness. The material properties of the sandwich plates follow a power-law distribution. The formulations are based on higher-order shear deformation plate theory and von Kármán geometric nonlinearity, and are solved using Galerkin’s method. Validation is achieved by comparing the results with published literature and finite element analysis (FEA). Artificial neural network (ANN) models are developed to predict natural frequencies without extensive computational runs, employing Bayesian Regularization (BR) and Levenberg–Marquardt (LM) algorithms in MATLAB. A new graphical user interface (GUI) tool facilitates frequency predictions using the proposed ANN model. Key findings indicate that modifications to the stepped face sheets and core layers affect stiffness, natural frequency, and vibration amplitudes. Increasing the core-to-total thickness ratio enhances stiffness, resulting in higher frequencies and reduced displacement amplitudes. The LM algorithm outperforms the BR algorithm, with errors generally below 1%, compared to 2% to 4% for BR with the log-sigmoid function. This study offers valuable insights into the design and analysis of FGM sandwich structures for engineering applications.

本研究探讨了由粘弹性地基支撑的功能分级材料（FGM）阶梯面夹层板（FGM-SPSFS）在爆炸荷载作用下的自由振动和瞬态动态响应。研究重点是几何配置和材料特性变化对各部分的影响。每块板由三层组成：一层均匀的硬芯和两层 FGM 面板，水平分为两段，面板厚度不同，在保持总厚度一致的同时增强了结构刚度。夹层板的材料特性遵循幂律分布。计算公式基于高阶剪切变形板理论和 von Kármán 几何非线性，并使用 Galerkin 方法求解。通过将结果与已发表的文献和有限元分析（FEA）进行比较，实现了验证。利用 MATLAB 中的贝叶斯正则化 (BR) 和 Levenberg-Marquardt (LM) 算法开发了人工神经网络 (ANN) 模型，无需大量计算即可预测自然频率。新的图形用户界面 (GUI) 工具有助于使用拟议的 ANN 模型进行频率预测。主要研究结果表明，对阶梯面片和芯层的修改会影响刚度、固有频率和振幅。增加芯层与总厚度的比率可提高刚度，从而提高频率并降低位移振幅。LM 算法优于 BR 算法，误差一般低于 1%，而使用对数-sigmoid 函数的 BR 算法误差为 2% 至 4%。这项研究为工程应用中的 FGM 夹层结构设计和分析提供了宝贵的见解。

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引用次数: 0

Simultaneous enhancement in deposition efficiency and nano-scale precipitation of high-strength AZ31 Mg alloy via water cooling assisted wire-arc directed energy deposition 通过水冷辅助线弧定向能沉积同时提高高强度 AZ31 镁合金的沉积效率和纳米级沉淀

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-09 DOI: 10.1016/j.tws.2024.112689

Pinkui Ma , Can Wang , Hailong Jia , Yihang Yang , Min Zha

The inter-layer cooling is crucial for adjusting microstructures and mechanical properties of wire-arc directed energy deposition (WA-DED) Mg alloys. In this study, AZ31 Mg alloy thin-wall components have been fabricated via WA-DED under different cooling modes: natural air cooling (AC) and side wall water cooling (WC) by an innovative WC equipment that provides water cooling on both sides of thin-wall components. The temperature variation during deposition process, microstructures and mechanical properties of AZ31 thin-wall components under different cooling modes (AC and WC components) have been systematically compared and analyzed. It shows that for thin-wall components with the same total deposition layers, the deposition time for the WC component is significantly reduced, i.e., the deposition efficiency of the WC mode has been much improved. Compared with the AC component, the size of both equiaxed and columnar grains in the WC component is finer, i.e., the average grain sizes of top regions in AC and WC components are ∼106.8 μm and ∼74.3 μm, respectively. Apart from (sub)micro-scale secondary phase particles formed during the solidification stage of molten pool, a large number of nano-sized precipitates have formed in the WC component because the cooling rate of molten pool of WC component is large enough in the post-solidification stage, while the AC component contains almost no nano-scale precipitates. Accordingly, the WC component exhibits excellent tensile properties, i.e., the yield strength and ultimate tensile strength along the build direction are ∼170 MPa and ∼250 MPa, respectively. At the same time, the elongation reaches 9.3 %. This study provides references for enhancing the deposition efficiency and improving mechanical properties of Mg alloy components.

层间冷却对于调整线弧定向能沉积（WA-DED）镁合金的微观结构和机械性能至关重要。在这项研究中，AZ31 镁合金薄壁部件是在不同的冷却模式下通过线弧定向能沉积（WA-DED）制造的：自然空气冷却（AC）和侧壁水冷却（WC）。系统地比较和分析了不同冷却模式（AC 和 WC 组件）下 AZ31 薄壁组件沉积过程中的温度变化、微观结构和机械性能。结果表明，对于总沉积层数相同的薄壁组件，WC 组件的沉积时间明显缩短，即 WC 模式的沉积效率大大提高。与 AC 组件相比，WC 组件中的等轴晶粒和柱状晶粒尺寸更细，即 AC 和 WC 组件顶部区域的平均晶粒尺寸分别为 ∼106.8 μm 和 ∼74.3 μm。除了在熔池凝固阶段形成的（亚）微尺度次生相颗粒外，由于 WC 组份的熔池在凝固后阶段的冷却速度足够大，因此在 WC 组份中形成了大量纳米尺度的析出物，而 AC 组份几乎不含纳米尺度的析出物。因此，WC 成分表现出优异的拉伸性能，即沿构建方向的屈服强度和极限拉伸强度分别为 ∼170 MPa 和 ∼250 MPa。同时，伸长率达到 9.3%。这项研究为提高镁合金部件的沉积效率和机械性能提供了参考。

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引用次数: 0

A systematical investigation on the impact of coupling crystal orientations on vibration characteristics of a single crystal superalloy cooling turbine blade 耦合晶体取向对单晶超合金冷却涡轮叶片振动特性影响的系统研究

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-09 DOI: 10.1016/j.tws.2024.112690

H.T. Li, X.M. Wang, H. Cheng, S.Y. Sun, W.Z. Yang

Revealing the dispersion mechanism of vibration characteristic is significant for turbine blade that is one of the most important hot components of aero-engine. Thus, the aim of this article is to systematically address the influence of primary and secondary orientation deviations on the dynamic responses of a single crystal blade by theoretical analysis in combination with finite element numerical calculation. Besides, the relationship between the crystal orientation in engineering and material science is clarified by a mathematical approach. Primary orientations characterized by two deviation angles, each having 16 directions and secondary orientations with 11 deviation angles are defined by three angles measured by the Laue method. Good agreement on variation of structural eigenfrequency for the first bending or torsional mode is attained between theory analysis and numerical calculation. Numerical results show that the primary orientation deviation direction could cause significant dispersion of the natural frequencies for low and high order modes. The increasing deviation angle widens the dispersion, with the maximum variation ratio of 5.62% for the torsional mode. Importantly, the conjunction with the secondary orientation could further changes the dispersion of the natural frequencies, and the maximum variation of 6.5% is achieved for the torsional mode. This research may provide new perspectives for substantially improving the resonance margin of single crystal turbine blades, with potential applications in preventing high cycle fatigue failure, which is very meaningful to guide the design of the aero-engine.

涡轮叶片是航空发动机最重要的热部件之一，揭示振动特性的分散机制对其意义重大。因此，本文旨在通过理论分析与有限元数值计算相结合的方法，系统地探讨一次取向和二次取向偏差对单晶叶片动态响应的影响。此外，本文还通过数学方法阐明了工程学和材料科学中晶体取向之间的关系。通过 Laue 方法测量的三个角度定义了以两个偏差角（每个偏差角有 16 个方向）为特征的主取向和以 11 个偏差角为特征的次取向。理论分析和数值计算在第一弯曲或扭转模式的结构特征频率变化方面取得了良好的一致。数值结果表明，主方位偏差方向会导致低阶和高阶模态固有频率的显著分散。偏差角度的增大会扩大频散，扭转模态的最大变异比为 5.62%。重要的是，与二次定向的结合可进一步改变固有频率的离散性，扭转模态的最大变化率为 6.5%。这项研究为大幅提高单晶涡轮叶片的共振裕度提供了新的视角，具有防止高循环疲劳失效的潜在应用价值，对指导航空发动机的设计意义重大。

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引用次数: 0

Plastic mechanism models for use in DSM localised loading design of hat sections 用于帽子截面 DSM 局部加载设计的塑性机理模型

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-08 DOI: 10.1016/j.tws.2024.112683

Zhehang Chen, Cao Hung Pham, Gregory J. Hancock

The Direct Strength Method (DSM) of design has been recently developed for the design of cold-formed steel members under localised loading. The method requires a yield load (P_y) and an elastic buckling load (P_cr) as input variables to the DSM design equations. This paper summarises test results used to develop plastic mechanism models for calculating P_y for hat sections subject to practical loading cases. All four loading cases, including Interior Two Flange (ITF), End Two Flange (ETF), Interior One Flange (IOF) and End One Flange (EOF) loading cases were investigated. The yield/plastic mechanism behaviour of multiple web sections is not yet fully understood, while several publications in the literature have discussed the mechanical behaviour of hat sections under localised loading. Hence, this paper explains and proposes a plastic mechanism model based on the experimental data for calculating the yield load (P_y) to be used in the DSM for localised loading design of hat sections in conjunction with the elastic buckling load P_cr.

最近开发了直接强度设计法（DSM），用于设计局部荷载下的冷弯型钢构件。该方法要求将屈服载荷 (Py) 和弹性屈曲载荷 (Pcr) 作为 DSM 设计方程的输入变量。本文总结了用于开发塑性机理模型的测试结果，以计算实际加载情况下帽形截面的 Py 值。本文研究了所有四种加载情况，包括内部两翼缘 (ITF)、端部两翼缘 (ETF)、内部一翼缘 (IOF) 和端部一翼缘 (EOF) 加载情况。多腹板截面的屈服/塑性机理行为尚未被完全理解，而文献中的一些出版物讨论了局部加载情况下帽子截面的力学行为。因此，本文解释并提出了一个基于实验数据的塑性机理模型，用于计算屈服载荷 (Py)，并将其与弹性屈曲载荷 Pcr 一起用于帽子截面局部加载设计的 DSM 中。

引用次数: 0

Vibration suppressing study of a simplified floating raft system by mixing using a nonlinear connecting intercalary plate and connecting nonlinear oscillators 通过混合使用非线性连接插板和连接非线性振荡器对简化浮筏系统进行振动抑制研究

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-08 DOI: 10.1016/j.tws.2024.112686

Qingchuan Zhan , Yilin Chen , Yuhao Zhao , Mingfei Chen , Rongshen Guo

To study the potential application of the mixing nonlinear vibration suppression of the floating raft system, a hybrid vibration control model of the simplified floating raft system with the nonlinear connecting intercalary plate (NCIP) and connecting nonlinear oscillators (CNOs) is established. Based on the correct dynamic behavior of the simplified floating raft system with the NCIP and CNOs, the vibration-suppressing characteristics and vibration-suppressing effect of the simplified floating raft system by mixing using the NCIP and CNOs are deeply studied and discussed. It can be found that the mixing use of the NCIP and CNOs can combine their advantages in an attractive way. The working states of the mixing use of the NCIP and CNOs are divided into linear and non-linear multiple frequency bands synchronously suppressing states, where the vibration island phenomenon is a sign of the NCIP and CNOs work on the non-linear state. Besides, the vibration of the simplified floating raft system under resonance regions can be suppressed at an attractive level, where the best vibration-suppressing ratios for single resonance regions and multiple resonance regions of the simplified floating raft system can be reached by selecting suitable stiffness parameter combinations of the NCIP and CNOs. Overall, the global vibration of the simplified floating raft system within a targeted frequency band can be suppressed synchronously and effectively by reasonable mixing use of the NCIP and CNOs, which play a potential role in the engineering application of strengthening the vibration-suppressing effect of floating raft systems in marine engineering.

为了研究混合非线性振动抑制浮筏系统的潜在应用，建立了简化浮筏系统与非线性连接插板（NCIP）和连接非线性振荡器（CNOs）的混合振动控制模型。在研究了带有 NCIP 和 CNO 的简化浮筏系统的正确动态行为的基础上，深入研究和讨论了混合使用 NCIP 和 CNO 的简化浮筏系统的抑振特性和抑振效果。研究发现，NCIP 和 CNO 的混合使用能很好地结合两者的优势。混合使用 NCIP 和 CNO 的工作状态分为线性和非线性多频带同步抑制状态，其中振动岛现象是 NCIP 和 CNO 工作于非线性状态的标志。此外，简化浮筏系统在共振区下的振动可以得到有吸引力的抑制，通过选择合适的 NCIP 和 CNO 的刚度参数组合，可以达到简化浮筏系统单共振区和多共振区的最佳抑振比。总体而言，通过合理混合使用 NCIP 和 CNO，可同步有效地抑制简化浮筏系统在目标频段内的全局振动，在海洋工程中加强浮筏系统抑振效果的工程应用中发挥了潜在作用。

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引用次数: 0